Scheduled system and method for processing chemical products

ABSTRACT

A processing system for processing a plurality of products, the system including a plurality of interchangeable units arranged to sequentially receive the products and each having a work station for effecting a specific operation on each of the products, the operation requiring a given time period; and wherein each work station accommodates simultaneously a predetermined number of the products, and the given time period and predetermined number associated with each unit are different than the given time periods and predetermined numbers of other said units. A transport system transports the products through the processing system so as to provide for each product a common occupancy time therein.

BACKGROUND OF THE INVENTION

This invention relates generally to product processing systems and, moreparticularly, to a system for processing products in chemicallaboratories and the like.

Automated laboratory systems are used widely to reduce the costs ofperforming multi-step chemical production and testing procedures. Manysuch systems employ a robotic device to move material, parts, tools orspecialized devices through variable programmed motions for theperformance of a variety of tasks. In a typical operation, a robot isone module of an operating system and would interact with several othermodules, which may be called work stations, to achieve the processing ofchemical samples. For example, pipette stations, liquid dispensingstations, diluting stations, washing stations and incubation stationsare typical stations. Examples of robotic processing systems aredisclosed in U.S. Pat. Nos. 4,510,684; 4,578,764; 4,586,151; 4,835,711;5,355,439 and 5,363,885.

The user of a robotic processing system first arranges processingstations in any convenient pattern and then instructs a robot in givenprocessing actions. Even though programming tasks, once understood by anoperator, are not intellectually challenging, the task of setting up asystem to operate efficiently is laborious. As the number of stations ina system increased, the number of variables to keep in mind to avoidcollisions and otherwise avoid conflicts in instruction made the tasklaborious even for those skilled in computer programming. In addition,many traditional robotic systems such as those used for drug screeningoperations utilize a single robotic device with a number of workstations, which perform operations requiring various time periods andmay be repeated several times in a complete process. Consequently, themovement of product samples requires complex looping and scheduling forefficient operation which typically is attained by maximizingutilization time of the robotic device. Product throughput of suchsystems is limited, therefore, by available robotic device time.

The object of this invention is to provide a robotic system whichsignificantly increase product throughput of chemical processes such asdrug screening.

SUMMARY OF THE INVENTION

The invention is a processing system for processing a plurality ofproducts, the system including a plurality of interchangeable unitsarranged to sequentially receive the products and each having a workstation for effecting a specific operation on each of the products, theoperation requiring a given time period; and wherein each work stationaccommodates simultaneously a predetermined number of the products, andthe given time period and predetermined number associated with each unitare different than the given time periods and predetermined numbers ofother said units. A transport system transports the products through theprocessing system so as to provide for each product a common occupancytime therein. The system provides improved products throughput.

According to one feature of the invention,at least some of the units areinterconnected in a rectilinear array that accommodates movement of theproducts in a rectilinear path. Orderly product movement is facilitatedby the use of a rectilinear product travel path.

According to a further feature of the invention each unit includes anelectrical connector automatically coupled to the connectors of adjacentunits in response to inter-connection thereof. Assembly of a system issimplified by this feature.

According to yet another feature of the invention, the connectors ofeach unit include a pair of connectors shaped and arranged forconnection with the connectors of straddling units and the connectorsare disposed in uniform locations of each unit. Unit interchangeabilityis further enhanced by uniform placement of connectors.

According to still another feature of the invention, the system is achemical screening system and the products are chemical assays. Thesystem is particularly efficient when used in chemical screeningapplications.

According to an additional feature of the invention, each unit issupported on rollers to provide mobility. The rollers simplify assemblyof a predetermined system arrangement.

According to another feature of the invention, the units include acorner unit connected to one end of the rectilinear array and shaped andarranged to provide movement of the products in a direction transverseto the rectilinear path. The corner unit facilitates assembly of asystem in a region having space limitations.

The invention also encompasses a method for processing products andincluding the steps of providing a plurality of interchangeable unitseach having a work station; interconnecting the units in a predeterminedserial arrangement; transporting the products between the units so as tomaintain in each work station a predetermined number of productsdifferent than the predetermined number of products in other workstations; effecting on the products in each work station a specificoperation, the specific operation in each work station requiring a giventime period different than the time periods required in other workstations; and controlling the transporting step so as to establish foreach product a common occupancy time in the system. The method permits asignificant increase in product throughput of the system.

According to another feature of the method, the interconnecting stepincludes the steps of interconnecting some of the units into a firstrectilinear array and interconnecting other units in a second arraydisposed transverse to said first array. The first and secondtransversely oriented arrays facilitate orderly product movement inconfined available space.

According to still other features of the method, the units areinterchangeable and each unit is supported on rollers to providemobility. System flexibility is enhanced by these features.

According to additional features of the method, the system is a chemicalscreening system, the products are chemical assays; the method includesthe steps of loading the chemical assays into individual receptaclesprior to the causing steps; and the operations include incubation,receptacle washing and reagent addition operations. The method isparticularly well suited for processing chemical assays of a drugscreening procedure.

DESCRIPTION OF THE DRAWINGS

These and other objects and features of the invention will become moreapparent upon a perusal of the following description taken inconjunction with the accompanying drawings wherein:

FIG. 1 is a perspective view of a robotic processing system according tothe invention;

FIG. 2 is a schematic top view of the system shown in FIG. 1;

FIG. 3 is a perspective view of a source unit of the system shown inFIGS. 1 and 2;

FIG. 4 is a perspective view of a transfer mechanism of the source unitshown in FIG. 3;

FIGS. 5a-5d are perspective views illustrating operation of a roboticdevice in one of the units of the system shown in FIGS. 1 and 2;

FIG. 6 is a schematic top view of a corner unit used in the system shownin FIGS. 1 and 2;

FIG. 7 is a perspective view of a discharge unit of the system shown inFIGS. 1 and 2;

FIG. 7a is a perspective view of lower portions of two adjacent units;

FIG. 8 is a schematic view of an isolation unit which can be used in thesystem shown in FIGS. 1 and 2;

FIG. 8a is a cross-sectional view of the isolation unit shown in FIG. 8;

FIG. 9 is a perspective view of another system unit embodiment of theinvention; and

FIG. 10 is a schematic view of a washing unit embodiment of the systemshown in FIGS. 1 and 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A robotic system 11 for executing a chemical screening process isillustrated in FIGS. 1 and 2. The system 11 can be used, for example, toperform immunosassays, cell-based reporter gene assays, homogeneousassays with multiple incubations, and the like. Forming the roboticsystem 11 are a plurality of separable, portable and interchangeableunits 12 arranged to sequentially receive assay products of thescreening process. One interconnected group of the units 12 are arrangedin a rectilinear array 15 that accommodates assay product movement in afirst rectilinear path. Another group of the units 12 is arranged in asecond rectilinear array 16 which accommodates assay product movement ina direction transverse to that provided by the first array 15. Joiningthe first and second arrays 15, 16 is a corner unit 12a. Each of theunits 12 includes a canopy 17 which engages the canopies of adjacentunits. Together the canopies 17 form an enclosed environmentallycontrolled chamber 19 in which the chemical screening process isperformed. A source unit 20 of the system 11 is connected to the initialunit 12 of the array 15.

As shown in FIG. 2, the units 12 include, in addition to the corner unit12a, an assay product entry an incubator unit 12b, washing units 12c,incubator units 12d, reagent dispensing units 12e a discharge unit 12fand a reader unit 12g. Each of the units 12b-12g includes a conventionalwork station 18 for effecting a specific operation on the assay productsbeing processed. For example, the work stations 18 of the washing units12c execute a washing operation, the incubator units 12d have carouselracks which accommodate incubation operations, the dispensing units 12ehave work stations 18 that effect a reagent dispensing operation and thereader unit 12g has a work station 18 that chemically analyzes the assayproduct at the conclusion of the screening process. It will beunderstood that the described work stations 18 are merely exemplary andthat units having work stations for providing other process operationscan be incorporated into the system 11.

The processing system 11 includes a transport system 21 for moving theassay products in a sequential manner through the units 12. Included inthe transport system 21 is a robotic device 23 individually associatedwith each of the units 12b-12g. The robotic devices 23 associated witheach unit 12 functions merely to transport assay products from apreceding unit to a succeeding unit. As described hereinafter, thetransport system 21 is programmed to provide for each assay product acommon occupancy time in the processing system 11.

The source unit 20 (FIG. 3) is coupled to the entry unit 12b of thesystem 11 but is isolated from the elongated environmental chamber 19 bya side wall 18 sealed to the canopy 17 of the entry unit 12b. Access tothe unit 12b is provided by an entry door 24 which can be opened andclosed by a conventional automatic actuator 25. Included in the sourceunit 20 are an assay supply section 26, a pipette supply section 27 anda test compound supply section 28. As shown in FIG. 3, the assay supplystation 26 includes a carousel rack 31 retaining a stack of assay plates32 and a robotic device 33 for handling thereof. A timer 34 controlsoperation of the robotic device 33. Similarly, the pipette supplysection 27 includes a carousel rack 36 retaining stacks of holders 37and a robotic device 38 for handling thereof. The test compound supplysection 28 includes a carousel rack 41 containing stacks of compoundplates 42 and a robotic device 43 for handling thereof. Straddled by thepipette source section 27 and the test compound source section 28 is atransfer station 45 shown in greater detail in FIG. 4. Structuraldetails of the carousel racks 31, 36 and 41 are known and such units areavailable commercially, for example, from Zymark Corporation ofHopkinton, Mass.

The transfer station 45 includes a turn-table 47 defining a plurality ofannularly distributed pockets 48. Functionally associated with theturn-table 47 is a liquid withdrawal and dispensing mechanism 49. Duringoperation of the system 11, the assay plates 32, the pipette tip holders37 and the compound plates 42 are selectively and sequentially movedinto and out of the pockets 48 by the robotic devices 38 and 43 in amanner described hereinafter. As shown in FIG. 4 each of the assayplates 32 defines an array of receptacle wells 51, each retaining anassay substance, each of the holders 37 retains an identical array ofpipette tips 52 and each of the compound plates 42 retains an identicalarray of receptacle wells 53 each retaining a test compound.

FIGS. 5a-5d depict sequential operations of the robotic devices 23. Asshown in FIG. 5a, each robotic device 23 has a pedestal 55 verticallyreciprocable on a vertically oriented, rotatable base member 56.Supported by the pedestal 55 is a horizontally reciprocable handlingmember 58 having a pair of reciprocable jaws 59. During operation of therobot 23 at each unit, the handling member 58 (FIG. 5b) first obtainsfrom a receiving position 62 established by a rotatable turn-table tray60 of its associated unit 12c, an assay plate 32 previously receivedfrom a preceding unit. The robot 23 then transports the assay plate 32to an input-output position 61 of the associated work station 18, asshown in FIG. 5c. After a specific process operation is completed at thework station 18, the robot 23 transports the assay plate 32 from theinput-output position 61 to a receiving position 62 on the succeedingunit 12e as shown in FIG. 5d. The tray 60 at each unit 12 can beprogrammed to rotate into a position which provides for a received assayplate 32 a desired changed orientation. For example, the tray 60 at eachunit 12 can rotate a received assay plate 180° so as to maintaintherefor the same orientation in each unit 12 of the system 11.Alternatively, re-orientation could be provided by a suitably designedrobotic device 23. To accommodate selective interchange of the units 12and simplify programming of the robotic devices 23, the receivingposition 62 of each unit 12 is disposed in a uniform geometricallylocated portion thereof.

The corner unit 12a of the system 11 also has a work station 18 andcooperating robotic device 23 as shown in FIG.6. In addition, the cornerunit 12a includes a tray 65 reciprocably and rotationally mounted on abase 66. In one position shown by solid lines, the tray 65 provides forthe unit 12a a uniform receiving position 62 accessible by its roboticdevice 23. The robotic device 23 functions as described above totransport an assay plate from the position 62 on the tray 65 to the workstation 18 and after completion of an operation therein returns theplate to the position 62. After return of the assay plate, the tray 65is moved to the uniformly disposed. receiving position 62 of thesucceeding unit 12d as shown by dashed lines in FIG. 6. Alternatively,the corner unit 12 can function merely to direct each assay plate 32from the rectilinear array 15 (FIG. 2) to the transverse array 16.

The discharge unit 12f which has an incubation work station 18 and arobotic device 23 is illustrated in FIG. 7. In addition, the unit 12fincludes an end wall 71 joined to its canopy 17 by a sealing flange 72.Defined in the end wall 71 is a discharge opening 74 and a door 75slidable between open and closed positions. The door 75 is opened by aconventional automatic control mechanism 70 after completion of anincubation operation in the work station 18 to allow the robotic device23 to pass an assay plate 32 through the discharge opening 74 to theuniform position 62 on the reader unit 12g (FIG. 2). As also shown inFIG. 7a, each of the units 12b-12h has on one side wall a pair of femaleelectrical connectors 77, 78 for transmission of, respectively,electrical power and communication signals. The opposite side wall ofeach unit retains compatible male electrical connectors 81, 82 that arereceived by the female connectors 77, 78 of an adjacent unit. Theconnectors 77, 78 and 81, 82 are disposed in uniform locations of eachunit 12a-12h so as to accommodate inter-changeability thereof andportability is enhanced by supporting rollers 84. In addition, the baseof each unit 12b-12f retains a computer 80 and an environmentallycontrolling electrical heater unit 86 which communicates with theelongated environmental chamber 19 via air input and output openings 87,88.

Illustrated in FIGS. 8 and 8a is an isolation unit 12h which can beselectively inserted into the system 11 when desired for certainscreening processes. The isolation unit 12h includes opposite side walls91, 92 that divide the space under its canopy 17 into an open volume anda closed compartment 93 isolated from the elongated environmentalchamber 19. Each of the side walls 91, 92 defines a pass through opening95 that accommodates transport of assay plates 32 between preceding andsucceeding units. The openings 95 are automatically opened and closed bysliding doors 96 operated by conventional automatic door actuators 97.Movement of assay plates 32 through the isolation unit 12h is providedby a transport mechanism 98 (FIG. 8a) which produces reciprocatingmovement of a rotatable tray 99 between an input receiving position 62(shown in dashed lines) to a receiving position (shown in solid lines)in a succeeding unit (not shown). After selective insertion into thesystem 11, the isolation unit 12h can segregate sections of theelongated environmentally controlled chamber 19 which require differentenvironmental conditions.

OPERATION

Prior to use of the system 11, the carousel rack 31 of the assay sourcesection 26 is filled with assay plates 32, the carousel rack 36 of thepipette source section 27 is filled with pipette tip retaining holders37 and the carousel rack 41 of the test compound source section 28 isfilled with compound plates 42. The timer 34 then is set manually toproduce operation of the robotic device 33 that sequentially moves assayplates 32 from the rack 31 to the receiving position 62 of the pipettesource section 27 at a predetermined rate of, for example, one perminute. In addition, each of the robotic devices 23 is programmed toreceive at the same predetermined rate a single assay plate 32 from apreceding unit 12 and to transport a single assay plate 32 to asucceeding unit 12. The selected transport rate of the individual assayplates therefore determines the throughput of the system 11. In thesource unit 25, the-robotic device 38 alternately and sequentially movesinto pockets 48 on the turn-table 47 assay plates from its receivingposition 62 and pipette tip holders 37 from the carousel rack 36. Therobotic device 38 also sequentially returns used pipette tip holders 37from the turn-table 47 to vacant positions in-the carousel rack 36. Inaddition, the robotic device 43 alternately and sequentially transportscompound plates 42 from the carousel rack 41 to selective pockets 48 onthe turn table 47 and transports therefrom completed assay plates 32through the open door 24 of the entry unit 12b into the receivingposition 62 thereof.

Upon registration of a tip holder 37 with the liquid withdrawal anddispensing mechanism 49 (FIG. 4), the array of pipette tips 52 iswithdrawn therefrom. Counter-clockwise rotation of the turn-table 47then produces registration of a compound plate 42 and the mechanismutilizes the pipette tips 52 to withdraw the content of the wells 53.The next step-wise and counter-clockwise rotation of the turn-table 47produces registration of an assay plate 32 and the dispensing mechanism49 dispenses the content of the pipette tips 52 into the wells 51. Asubsequent counter-clockwise step rotation of the turn-table 47 movesthe completed assay plate 32 from a registration position into aposition accessible to the robotic device 43 which transports thecompleted assay plate 32 to the entry station 12b. Simultaneouslytherewith, the mechanism 49 loads the used pipette tips 52 into an emptyregistered holder 37. Such operation of the source unit 20 continues toproduce entry into the entry unit 12b of an assay plate 32 at timedintervals established by the timer 34.

During movement of assay plates 32 through the system 11, (FIG. 2) eachrobot 23 moves assay plates from preceding to succeeding units 12 at theselected rate. The only communication required between adjacent units 12are signals indicating that an assay plate 32 is available for transportto a succeeding unit or that a position 62 is available to receive anassay plate 32 from a preceding unit. To accommodate the selected assayplate transfer rate, each of the individual units 12b-12f is providedwith a work station capacity dependent upon the time period required forcompletion of its process operation. Thus, the incubation rack of anincubation unit 12d requiring a relatively lengthly incubation periodtypically will simultaneously accommodate a number of assay platesgreater than the number of assay plates simultaneously accommodated bythe work stations 18 of either a washing unit 12c or a reagentdispensing unit 12e which require shorter time periods for completion oftheir process operations. The desired assay plate capacity can beprovided in an individual unit by combining available standardprocessing units of smaller capacity. Because each unit 12b-f isprovided with an individual robotic device 23 responsible only for assayplate movement associated with a single process work station, the system11 can provide a throughput much greater than possible with priorrobotic processing systems.

Illustrated in FIG. 9 is another embodiment unit 101 for use in thesystem 11. The unit 101 is identical to the units 23 except that it isprovided with a discharge position 102 accessible to the robotic device23 of a succeeding unit rather than the receiving position 62 of theunits 12. As in system 11, however, the position 102 is established by aturn-table disposed in a geometrically located portion of each unit 101so as to enhance therein interchangeability in a complete system.

FIG. 10 schematically depicts some of the operational components of awashing unit 12c of the system 11. Mounted under the canopy 17 above thestation 18 is a conventional washing head 111 which includes a fluidpump 112. The washing head 111 functions to wash out of the wells 51 ofan assay plate 32 (not shown) an unwanted portion of their content.Removed material and wash water 115 together with incidental air fromthe chamber 19 are circulated by the pump 112 via a tube 113 into acatch reservoir 114 disposed in the lower portion of the unit 12c. Washwater is circulated to the head 111 from a tank 121 by a pump 122. Theenvironmentally conditioned air removed by the pump 112 is withdrawnfrom the reservoir 114 via a tube 116 by a vacuum pump 117 and returnedto the chamber through a tube 118. Accordingly, loss in the washing unit12c of environmentally conditioned air is prevented.

Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. It is to be understood,therefore, that the invention can be practiced otherwise than asspecifically described.

What is claimed is:
 1. A processing system for processing a plurality ofproducts, said system comprising:a plurality of interchangeable unitsinterconnected in a series arrangement to sequentially receive theproducts and each having a work station for effecting a specificoperation on each of the products, said operation requiring a given timeperiod; and wherein each said work station accommodates simultaneously apredetermined number of the products, and said given time period andpredetermined number associated with each said unit are different thansaid given time periods and predetermined numbers of other said units;and wherein said predetermined number and given time period of each unitare such as to accommodate for each unit a selected product throughputrate; and a transport system for sequentially transporting the productsthrough each of said units at said selected throughput rate so as toprovide for each product a common occupancy time in the processingsystem.
 2. A processing system according to claim 1 wherein at leastsome of said units are interconnected in a rectilinear array thataccommodates movement of the products in a rectilinear path.
 3. Aprocessing system according to claim 2 wherein each said unit compriseselectrical connector means automatically coupled to said connector meansof adjacent units in response to interconnection thereof.
 4. Aprocessing system according to claim 3 wherein said connector means ofeach unit comprise a pair of connectors shaped and arranged forconnection with said connectors of straddling units.
 5. A processingsystem according to claim 4 wherein said connectors are disposed inuniform locations of each unit.
 6. A processing system according toclaim 5 wherein the system is a chemical screening system and theproducts are chemical assays.
 7. A processing system according to claim6 wherein each said unit is supported on rollers to provide mobility. 8.A processing system according to claim 7 wherein said units include acorner unit connected to one end of said rectilinear array and shapedand arranged to provide movement of the products in a directiontransverse to said rectilinear path.
 9. A processing system according toclaim 1 wherein each said unit comprises electrical connector meansautomatically coupled to said connector means of adjacent units inresponse to interconnection thereof.
 10. A processing system accordingto claim 9 wherein said connector means of each unit comprise a pair ofconnectors shaped and arranged for connection with said connectors ofstraddling units.
 11. A processing system according to claim 10 whereinsaid connectors are disposed in uniform locations of each unit.
 12. Aprocessing system according to claim 11 wherein said units include acorner unit connected to one end of said rectilinear array and shapedand arranged to provide movement of the products in a directiontransverse to said rectilinear path.
 13. A processing system accordingto claim 12 wherein said units include a corner unit connected to oneend of said rectilinear array and shaped and arranged to providemovement of the products in a direction transverse to said rectilinearpath.
 14. A processing system according to claim 1 wherein the system isa chemical screening system and the products are chemical assays.
 15. Aprocessing system according to claim 1 wherein each said unit issupported on rollers to provide mobility.
 16. A method for processingproducts and comprising the steps of:providing a plurality ofinterchangeable units, each having a work station; interconnecting saidunits in a predetermined series arrangement; transporting the productssequentially through said units so as to maintain in each said workstation a predetermined number of products different than thepredetermined number of products in other said work stations; effectingon the products in each said work station a specific operation, saidspecific operation in each said work station requiring a given timeperiod different than the time periods required in other said workstations; and wherein said predetermined number and given time period ofeach unit are such as to accommodate for each unit a selected productthroughput rate; and controlling said transporting step so as toestablish said selected throughput rate for each unit and provide foreach product a common occupancy time in said system.
 17. A method forprocessing products according to claim 16 wherein said interconnectingstep comprises the steps of interconnecting some of said units into afirst rectilinear array and interconnecting other said units in a secondarray disposed transverse to said first array.
 18. A method forprocessing products according to claim 17 wherein each said unit issupported on rollers to provide mobility.
 19. A method for processingproducts according to claim 16 wherein the system is a chemicalscreening system and the products are chemical assays.
 20. A method forprocessing products according to claim 19 including the steps of loadingsaid chemical assays into individual receptacles prior to saidtransporting steps, and wherein said operations comprise incubation,receptacle washing and reagent addition operations.